Aeroplane-wingr



. E. V. CROWELL AND W; HAWKINS.

AERO'PLANE WING cousmucnou.

. I v APPLICATHJN FILED FEB-10,192l- 1,4:12,455. Patented Apr. '11,1922.

2 gig. Z 5 Z927 g5 a I If 1/ f 25) 4 l6 7g ATTORNEYS UNITED STATESPATENT OFFiQE.

ERD v. CROWELL AND WHITEMAN HAWKINS, or TULSA, OKLAHOMA.

'AEROPDANE-WING CONSTRUCTION.

Specification of Letters Patent. Patgnted A 11 1922 Application filedFebruary 10, 1921. Serial No. 443,875.

at the will, and under the control, of the operator. The term win-gcurve is well 15 7 known in practical aerodynamics, having reference tothe cross section of an aeroplane wing, particularly form or contour ofthe lower surface of a wing.

It .is a well known fact that among the qualities necessary in acommercial aeroplane, the two most important or outstanding. are firstits ability to take the air from, and land within, a confined space,coupled with horizontal stability at low speeds, with a useful load, andsecond extreme speed with :minimum power consumption. These twoqualities however have been found to require materially different wingcurves and it is the common practice of wing construction at'the presenttime to produce a wing having a curvature iesembling to the great estpossible extent those curvatures necessary a stance is to provide in oneconstruction for for the two qualities above outlined. This 1 practiceresults in a wing without extreme lifting power and without extremespeed, and. our primary object in the present inboth extreme lift andextreme speed.

In a wing construction providing for extreme lift and maximum stabilityat low "speedswith useful loads, carrying with it the ability to takethe air fromi or land within, a confined space, it is necessary that thewing be deeply concaved adjacent to its forward edge upon its lowersurface and thisform of wing curve sets up considerable resistance tospeed, commonly referred tov as drag. On the other hand a wing designedfor speed requires a substantially flat lower surface and it is ourpurpose to permit ofanswering these requirements by a; wing having adeeply conea-ved lower surface which may be straightened out into a"substantially flat line for the purpose of eliminating the drag and thuspermitting of maximum speed with minimum power.

It becomes quite obvious that with other things equal the concaved wingcurve requires increase of horse power and area of wing surface in orderto accomplish speed and it is also quite obvious that the commonpractice of piling on horsepower and wing area is a decided drawback inacommercial machlne, bothon the account of increased first cost and ofsubsequent maintenance.

In proposing our present construction therefore we seek to avoid thedisadvantages of the ordinary practice and produce the desired resultsin a simple economical and efiicient manner.

For the purposes of our invention we propose a wing web or rib, of whicheach wing may include any number, provided-with means controlled by theoperator whereby the lower edge may be flexed from a substantiallystraight line into a concavely curved line and vice versa.

In the accompanying drawing which illustrates our invention and forms apart of this specification,

Figure 1 is a side elevation of our improved wing web or ribshowing thesame the slide housing at the rear end of the rib or web.

-Referring now to these figures our invention proposes a wing rib or webwhose body 10 is rigid and has a decided arch adjacent to its forwardendill producing a deep concave 12 upon its undersurface, the entirebody tapering from its front end 11. to its rear end 13, the latter ofwhich is provided with a rigid housin 14 also of tapering form. V

The rib or web 10 which may have a lengthwise series of longitudinallyslotted openings 15, provides as usual for the reception of wing beams16 and 17 which determine the length of the wing and extend transverselythrough a number of ribs or Webs 10 in the finished wing structuredepending in number upon the desired length.

' According to our invention the rib or web is provided along its loweredge with a series of jointed strips 18 whose beveled ends are inabutting relation, and the rear.

I j'oints between theseveral strips 18 attached thereto, isimovable'into. the concave 12. of the body 10, against and parallel with-thelower edge of the body, as seen in Figure 1, and is also shiftable intoa straight line from the front tov the rear of the bodyl0;across theconcave-12 as shown: in-Figure 2.

Fonthis purpose swinging. side links 21 '2 ,are: pivotally attached at,their upper ends to opposite sides of-the web or rib 10. at the I rearofits conca've l2 and arepivotally attached at their lower ends; tocertainof the strips 18, and atspaced points ofthat portionof the'fiexiblemember formed=bythe vstrips;18 and their connecting strap 19 op-'posite; the concave 112 of-the,rigid body of the rib or web, the strips18- having. laterally extending pins 22 projectingthrongh th arcuateslots 23 of cam plates 24%, these plates being .pivotally mounted at 25t0 the rigid body 10 and connectediby a'link, or connecting rod 26 so asto constrain the same to simultaneous movement. Shifting of these cammembers 24 in one. direction serves to draw the pins 22 upwardl inviewofthe eccentricity of the slots 23 in respectto the pivots 25, asshownin Figure 1. Y e

The connections for actuating the cam 4 plates 24 may include anysuitable means as for instance a lever27 pivotally mounted at28 onaportionof each webor riband having a connecting rod 29 extending fromone, end to the foremost cam plate 24,:16V6I 27 beingconnectedintermediate its ends by a pivot 30 with an arm 31 projectingthrough one of theslots 15 of the .rib and 'in.turn;connected either toadjacent ribs or to a manual lever (not shown) by rods-32.

' It isthus obvious that as the 'camplates are shifted from the positionof :Figure 1 for maximum stability and lifting powernto the position ofFigure 2 for maximum speed,

therear end of the strap 19 recedes rearwa-rdly into the housing 1443sit assumes a straight line, and that in theopposite movement, namely vto .the position vof Figure 1 it is drawn forwardly in order to give.the re-i.

quired extra length necessary in order to .follow the curvature oftheconcave underpor-tion of the rib. i

' means of ,our invention, and in view of the .factthat the material ofwhich the wing surface is formed is .flexible in its nature and capableof attachment to ,the strap 19 air or landing and then shift the partsto the speed position of Figure 2 when the ,machine-iis straightened outin horizontal flight.

Our invention thusanswers the two-major requirements as far as Wingstructure is concerned, withoutincreasing wing :area and likewise,WlthOllt increasmg motive power.

It is .OlEJVlOllS. that: many changesumay be ..made, and asto theflexible'metal strap .19 joining the strips :18, .ientire dependenceneed notwbewplaced uponsuch astrapibut the strips. 18, may behingedlyconnected at their endsto one another if it-xis so "desired orif it isvfoundin practice that theconstant fiexure ior bending istoogreat'for; the metal strap alone to be. depended upon. Furthermore-,although wexhaveshowniand described certain means including a'lever 27for:actu' ating the cam plates, aother: means. may-be utilized includingfor instance .cam shafts extending the full length 'ofthe wingandconnecting and aactuating the several cam plates of the several-ribswithinithewing.

We claim:

1. A ,web for aeroplane wings comprising a rigid body :havin a lowerconcavely curved ved e, a flexible cover supporting member a ongsaidedge, and :means for flexing said -member into and out of theconcave of the body, includin cam members mOuntedatlengthwise spacepoints of the body and having-operative connection with the said. memberat lengthwise spaced points of the latter.

2. A web'for aeroplane wingscomprising' va rigid body having :a .lowerconcavely curved edge, and a flexible member extending along said edgeand ishiftable into and out of the concave thereofisaid memberconsisting of -a length-wise series of strips 7 havingbeveledabuttinends, and a flexible ich said strips are continuous strap to wconnected; i

3. A web for aeroplane wings comprising a rigid bodyhaving'its'loweri-edge provided with a'concavely curvedportion, and.alflexible strip extending continuously along said edge having a rearsliding-portion and a forward portion yieldable into and out of the saidconcaved portion, said bodyhaving a housing member at its rear endinwhich the rear' end of the rear sliding portion of said flexible stripis -movably supported.

LIA web for aeroplane wings comprising a rigid body having its loweredge provided with a .concavely curved portion, a pair of cam-platesconnected to one another and pivoted to the said bod and provided witheccentrics n s, a flex e strip extending along the lower edge of thebody and having outstanding pins projecting into the slots of said camplates for shifting movement thereby into and out of the concavedportion, and means for moving said cam plates in opposite directions.

5. A web for aeroplane wings comprising a rigid body having its loweredge provided with a concavely curved portion, a pair of cam platesconnected to one another and pivoted to the said body and provided witheccentric slots, a flexible strip extending along the lower edge of thebody and having outstanding pins projecting into the slots of said camplates for shifting movement thereby into and out of the concavedportion, and means for moving said cam plates in opposite directions,said flexible strip being secured at its forward end to the forward endof the web, and a housing member at the rear end of the web in which therear end of the strip is movably supported.

ERD V. CROWELL. VVHITEMAN HAWKINS.

